General aviation aircraft often sit unattended for extended periods of time. Because such aircraft are often equipped with expensive avionics, these unattended aircraft are an inviting target for vandals and thieves. The door locks provided as standard equipment on many general aviation aircraft are largely ineffective against even amateur thieves and can be opened with a simple screwdriver in a matter of moments. Accordingly, there is a need to provide a locking device for general aviation aircraft which can be installed on new aircraft or easily retrofitted to existing aircraft, to secure the aircraft cabin and its contents against unauthorized entry.